The Digital Living Network Alliance (DLNA for short) is a nonprofit organization initiated by SONY, Intel and Microsoft, and aims to solve the sharing of digital media contents between consumer electronic devices. The DLNA uses a Universal Plug and Play (UPnP for short) protocol to discover, describe and control devices. On basis of this, various roles of the DLNA device are defined: a Digital Media Server (DMS for short), a Digital Media Player (DMP for short), a Digital Media Controller (DMC for short), and a Digital Media Renderer (DMR for short).
The DMS and DMR, as basic device types of the UPnP, may broadcast its own online information and description information to the network through a Simple Service Discovery Protocol (SSDP for short), so as to enable the DMC to play the media contents shared by the DMS on the DMR or enable the DMP to play the media contents shared on the DMS. The communication protocol therebetween may be a HyperText Transfer Protocol (HTTP for short), and may be carried by using a User Datagram Protocol (UDP for short) or a Transmission Control Protocol (TCP for short), for example, the SSDP uses HTTP over UDP, and HTTP over TCP is used to acquire the device description information and service description information as well as subsequent device control.
The DLNA network generally is a local area network environment in a home environment, or an operating network or public network of the same subnet, and the method for sharing media resources of the DLNA cannot be used currently for the wide area network or a network of different subnets. Therefore, the DLNA sharing is only limited in a local range, it is not expanded to sharing on the internet, and it cannot be more widely applied.
There is no effective solutions currently for the problem in the related technologies that the DLNA sharing is only limited in a local range.